Did you get your low voltage issue sorted?
Are you getting decent sparks? It's an easy check so long as you remember to let it jump to the cylinder head rather than the insulated cam cover.
Check the fuel level in the carbs. If none of those show a problem I'd guess it's a case of getting the carbs off for a good clean/blow-though of the jets and passageways.
Edit: does it "get through" the rough running at higher revs? If not, a faulty fuel pump/clogged filter may simply be causing fuel starvation.
Are you getting decent sparks? It's an easy check so long as you remember to let it jump to the cylinder head rather than the insulated cam cover.
Check the fuel level in the carbs. If none of those show a problem I'd guess it's a case of getting the carbs off for a good clean/blow-though of the jets and passageways.
Edit: does it "get through" the rough running at higher revs? If not, a faulty fuel pump/clogged filter may simply be causing fuel starvation.